This is the only calcium/vitamin D/magnesium product I could find that had magnesium citrate and not magnesium oxide which I have problems with. So far, I am happy with the production. However, please be advised that you need to shake the bottle really really well or you will end up with sludge at the bottom. Also the bottle is very drippy. You'll need to rinse it off after pouring each dose or else keep it sitting on a folder paper towel.